【摘要】 本文对ＴｉＡｌ合金激光表面合金化表面改性层中ＴｉＣ生长形态的生长过程及机理进行了研究，发现在冷却速度为１０２℃／ｓ量级的准快速凝固条件下，ＴｉＣ型ＭＣ碳化物在微观上具有极为规则“砖块分叉堆砌”生长特征的发达树枝状生长形态，其生长机制是密排面生长台阶沿双“之”字形轨迹侧向推进的“砖块分叉堆砌”生长机制更多还原

【Abstract】 The growth morphology and mechanism of a MC carbide (TiC type) under quasi-rapidsolidification conditions of laser surface alloyed coatings on a titantium aluminide alloy are studied. TheMC carbide under quasi-rapid solidification conditions with a cooling rate of about (4 10~2) C /s is foundto have an unique dendritic morphology having strong faceted and brick-stacking growth characteristicson dendrite arms. The growth mechanism is a brick-stacking/ double-zigzag micro-branching mechanismoriginating from lateral growth on the intersecting {111} planes.更多还原